Omar - When you say sub-divided Bar Views, do you mean 'paned' Bar Views with multiple lines of comparable bars, or 'stacked' bars, where each bar has a series of smaller regions inside?
If you mean stacked, then you can order the stacks within the bars using:
Bar View: View Toolbar: Tools > Order > Order stacks (under Order bars)
If you mean paned bars, there is also an option to order the vertical panes lower on this menu.
Perhaps you could post a sample file illustrating the ordering you are trying to achieve?